The present invention relates to a method for producing patterned or textured glass, and more particularly to a method for patterning or texturing the surface of glass manufactured according to the float process.
As is known in the art in the manufacture of glass by the float process, molten glass is poured at controlled rates onto a molten metal bath, such as tin, to form a continuous ribbon of heat softened glass. The heat softened glass ribbon is then drawn across the metal bath while the ribbon is cooled along its length to produce a structurally integral sheet of glass. The ribbon or sheet is then withdrawn from the surface of the molten metal bath into an annealing lehr where the glass is then heat treated in a conventional manner.
With the float glass process, the only type of glass in practice which is generally produced is glass with plain parallel fire-polished surfaces. For the production of glass with patterned or textured surfaces, use has generally been made of either the so-called rolling method in which the glass strip or ribbon is formed at high temperatures by a pair of rolls which have an embossed roll surface which acts upon the glass surface, or the transparent glass sheet is superficially treated while cold by etching, sand blasting or other suitable surface treatment so as to produce the ornamental form of glass product desired.
Also, more recently, processes have been developed for patterning or texturing the surface of glass when the ribbon is in the float chamber on the molten bath. These processes have involved the use of a non-adhesive friction tool which is moved across the ribbon to roughen its surface or the use of gas jets within the float chamber which direct gas at the moving glass while the glass is still soft enough to displace portions of its surface. In both of these more recent methods the patterning or texturing of the surface takes place while the glass ribbon is heat softened and then the ribbon is cooled to preserve, at least partially, the patterning or texturing that has taken place.